Household refrigerators of the cycle defrosting type



A ril 14, 1959 v L. G. BECKETT m 2,881,601

HOUSEHOLD REFRIGERATORS OF THE CYCLE DEFROSTING TYPE Filed Jan. 24, 1957 7 Sheets-Sheet 1 m @a \b i INVENTORS L60 zf kc'fib BY Rajmon 5:73.5 3

April 14, 1959 L. G. BQECKETT ETAL 2,881,601

HOUSEHOLD REFRIGERATORS OF THE CYCLE DEFROSTING TYPE Filed Jan. 24, 1957 '7 Sheets-Sheet 2/ INVENTORS Lee G Beckebt 905 m on d E Tobej April 14, 1959 L. BECKETT ETAL HOUSEHOLD REFRIGERATORS OF THE. CYCLE DEFROSTING TYPE Filed m. 24, 195'! -S 95. 7 Sheets heet 3 INVENTORS L/ao G! Bea/(e i K Raymond E. Tbby ff Zuz ndi, f1 f f orne c/ April 14, 1959 2,881,601

HOUSEHOLD REFRIGERATORS OF" THE CYCLE DEFROSTING TYPE L. G. BECKETT ET AL 7 Sheets-Sheet 4 Filed Jan. 24, 1957 INVENTORS L1 20 G, B ckett Raym and E. 'Bbey Qdkni fliforney April 14, 1959 G. BECKETT ETAL 1 HOUSEHOLD REFRIGERATORS OF THE CYCLE DEFROSTING TYPE I 7 Sheets-Sheet 5 Filed Jan 24, 1957 I INVENTORfi be 0 6; Be cke t t b ,Qaymond 5.7510 29 Q QM/Lt j, 20ml: ,(ZTor/My April 14,- 1959 I L.'G. BECKETT ET AL HOUSEHOLD REFRIGERATORS OF THE CYCLE DEFRO'STING TYPE Filed Jan. 24, 1957 '7 Sheets-Sheet 6 INVENTOR.

J m w r u ew k. Bd W m ow a bRfi M R A ril 14, 1959 L. G. BECKETT EI'AL 1,

HOUSEHOLD REFRIGERATORS OF THE CYCLE DEFROSTING TYPE Filed Jan. 24, 1957 7 Sheets-Sheet '1 INVENTORS Lee G. Beckett Raymohc/E.Tobey United States Patent 0.

HOUSEHOLD REFRIGERATORS OF THE CYCLE DEFROSTING TYPE Leo G. Beckett, Henderson, Ky., and Raymond E. Tobey, Evansville, Ind., assignors to Whirlpool Corporation, a corporation of Delaware Application January 24, 1957, Serial No. 636,091 2 Claims. (Cl. 62-287) The present invention relates to household refrigerators of the cycle defrosting with refrigerators of the type having a below-freezing chamber for frozen food and ice, and having an above freezing chamber for the storage of other food. l

One of the objects of the invention is the provision of an improved household refrigerator in which the frozen food chamber is constantly maintained at a temperature below freezing, and the above-freezing storage chamber is constantly maintained at a suitable temperature without over-cooling, and the evaporator for the latter chamber is periodically defrosted once over-heating the food contained therein.

Another object of the invention is the provision of an improved household refrigerator of the class described having means for constantly disposing of condensate, and having a freezing chamber in which the amount of frost is reduced to a minimum, so that defrosting of the freez; ing chamber can be accomplished by scraping or defrost} ing which is required only at long intervals'of time.

Another object of the invention is the provision of an improved household refrigerator which is simple in construction, efficient, which constantly maintains the in tended temperatures in its respective chambers, which has storage space at suitable temperatures for all of the different kinds of foods utilized in the'horne, which is type, and is particularly concerned corner for providing space for during each cycle without adapted to be manufactured cheaply, and 'which may be 7 used for a long period of time without necessity for re pair or replacement of any of its parts. I

Other objects and advantages of'the invention will'be apparent from the following description and the accompanying drawings in which similar characters ofreference indicate similar parts throughout the several views.

'1 Referring to the seven sheets'of drawings accompanying the specification, I

Fig. l is a front elevational view of a household'refrigerator embodying the invention; Fig. 2 is a vertical sectional view taken on the plane of the line 2-2 of Fig. 1, looking in the direction of the arrows;

Fig; 3 is a front with the door open;

Fig. 4 is a front elevational tor assembly; 7

Fig; 5 is aside elevational view of the evaporator assembly;

Fig. 6

system; v I

Fig. 7 is a rear elevational view of the condenserand compressor assembly; I Fig. Sis a top plan view of the assemblyof Fig. 7;

elevational view of the refrigerator view showing the evapora is a diagrammatic view of the refrigeration Fig. .9 is a side elevational view of the compressorcondenser assembly; 10 is a top 'assem'bly. I i Referring to Figs. 1 to 3, 20 indicates in its entirety a'household refrigerator" embodying the invention, and

plan view of the upper condenser Patented Apr. 14, 1959 "ice The shell 27 has a forward, inwardly extending face flange 33 extending all about the door opening at the sides and bottom, and the transverse partition 26 is'provided with a breaker strip 34, also serving as a face flange between the compartments.

The cabinet has an inner liner 35 which may consist of a metal shell of box-like shape having a rear wall 36, top wall 37, bottom wall 38, side walls 39 and 40, and a diagonal wall 41 at the rear bottom corner.

The outer shell 27 also has a rear panel 42, which is provided with a concave recess 43 at the bottom rear the motor compressor unit 44.- The space between the outer shell 27 and inner liner 35 is filled with fibrous insulation, such as rock wool or glass wool contained in moisture tight polyethylene bags, adapted to maintain the insulation in a dry condition of high insulating value.

The lower wall 38 of the inner liner 35 drains toward a central drain aperture 45, connected by a rubber hose 46, with a bottom drain fixture 47 for carrying any condensate that drains to the bottom 38 to a condensate pan 48. The bottom panel 32 of the outer shell is provided with a plurality of pressed metal feet 49, welded to the bottom panel and provided with threaded levelling screws 50, except that the front levelling screws 51 are preferably disposed toward the front end of the bottom panel 32 to support the additional weight which results from the use of door shelves having articles stored therein. I

The space between the outer shell and inner liner 35, about the door opening is closed by heat insulating breaker strips 52-57, including also the breaker strip 34 that extendsacross' the front of the cabinet between the doors.

The upper breaker strip 57 may support the cold control which also serves as an automatic defroster, and

Y comprises the usual bellows actuated switch, the bellows being connected by a capillary tube to a bulb filled with refrigerant and located on the upper evaporator for cooling the below-freezing storage chamber 25. 4

The insulating partition 26 may comprise a metal box of substantially rectangular shape carried by the side outside of the refrigerator, where the pipe 60 extends downward to discharge condensate in the condensate pan 48.

The doors 22 and 23 may be of similar construction in that each door comprises an outer metal shell and an inner plastic liner. For example, the upper door 22 comprises an outer metal shell 61, having rearwardly extending side flanges 62, which are turned inwardy and secured to a molded insulating inner door panel 63, which is overlapped by the inwardly extending flanges.

A door seal 64 of rubber is secured between the inner and outer panels of the door and has a resilient portion for engaging the face flange 33 on the cabinet. The space between the inner and outer panels of the door is filled with suitable insulation 65 of the same type previouslydescribed, and the inner panel 63 is preferably formedwith 3 an inwardly extending rectangular ridge 66, which provides a frame for a plurality of integral shelves 67, 68, 69, and a container 70 for butter or the like having a cover.

Each of the shelves 67-69 preferably has a transverse band 71, 72, 73, each of which is provided with inwardly extending end flanges 74 at each end, secured to the inside of the ridge 66 to retain the food stored on the shelves.

, The lower door 23 also comprises an outer metal shell 75 and a similar inner molded plastic door panel 76, joined together at overlapping flanges which carry the rubber door seal 77, extending completely about the lower door at its inner face for engaging the face flanges 33 about the lower compartment 25. p The lower door panel 76 may be formed with an inwardly projecting rectangular ridge 78 framing the re"- cesses which are formed by the shelves 79 and 80, having transverse retaining bands 81 and 82.

As both of these shelves are located opposite the freezing chamber 25, they are preferably used for storing frozen food. The doors are each provided with suitable door latches 83, 84, for engaging keepers 85, 86, carried by the cabinet and actuated by handles 87, 88.

Each of the doors is hingedly mounted by door hinges 89, 89 and 90, 90. The lower freezing chamber 25 is provided with a freezing evaporator 91, comprising an upper Shelf 92, vertical back wall portion 93, and a diagonal portion 94. The shelf 92 is spaced sufliciently from the partition 26 to support ice trays 95.

The side wallsof the freezer chamber 25 are provided with channeled guides 96 for slidably supporting a wire basket 97, having side walls, rear wall, and front wall, and a bottom wall formed of wires welded together and open at the top. The lower rear corner of the basket 97 conforms to the shape of the evaporator at 94 by having a diagonal wall at that point.

The upper food storage chamber is provided with-an upper. evaporator 98 comprising a sheet metal member having a rearwall 99 and two forwardly extending side walls 100, and 101, secured to the inner liner 35 .at the top of the above-freezing compartment 24.

Theupper evaporator 98 is spaced from the liner walls which arexprovided with drain troughs 102 on both side walls, and drain trough 103 on the rear wall leadingto acentral discharge aperture 104 which drains into a funnel 105, communicating by means of a suitable conduit 106 with a down conduit 107, also discharging in the condensate pan 48.

Theside walls of.the liner 35 are provided with suitable studs 108 for supporting a wire shelf 109, andalso. studs 110 for supporting an upper wire shelf 111.

Wire shelf .1 09. may slidably support a drawer 112 having a suitablecover 113 for storing various types of food at above-freezing temperature. The liner may also support guides I14 and a center post 115 with a'guide for slidably supporting the drawers 116 and 117, serving as a crisper and for meat storage, and provided with suitable covers 118, 119. Referring to Figs. '4 and 5, these are assembly views of the upper and lower evaporators employed, the upper evaporator being indicated by 98 and the lower evaporator by 911' The parts of the lower evaporator are again indicated at 92-94, comprising a rectangular sheet of alum'i num which has been bent toprovide the upper shelf '92; rear wall 93, and diagonal wall 94.

The upper shelf 92 is bordered at each side by an up-' wardly extending flange 120, and at the front by a'downwardly extending face flange 121.

An elongated aluminum receiver 122, having spun tapered ends'123, 124, is mounted on the top shelf 92 and secured by clamping bands 125. The lower evaporator 91 hassinuous tubing located on its rear wall 93, and'di'agonal' wall 94 weldedto these walls and'als'o secured by clips 126, and this tubing may comprise a plurality of horizontal passes 127-133 joined at their ends by the U- shapedformations 134,135, and the inlet for this evaporator is at the left end of the evaporator indicated by the reduced portion 136 for connection to a capillary tube.

From the sinuous coils on the back wall the tubing extends upward at 137, and is arranged with sinuous passes of a similar nature indicated at 138-141 on the lower side of the top shelf 92, extending at 142, which is the outlet of the lower evaporator and is connected by tubing 143 to the upper evaporator 98.

The lower evaporator is in unrestricted communication with the upper evaporator 98 through tubing 143, which extends to a horizontal rearward pass 144 on the upper evaporator. From 144 a pass 145 extends across the back wall and forwardly at 146, upwardly at 147, and backwardly at 148.

From 148 there is a horizontal pass 149 which extends forwardly at 150, downwardly at 151, and backwardly at 152, this being the outlet of the upper evaporator.

All of the passes of the upper evaporator are on the outside, spacing the sheet metal of the upper evaporator 98 from the liner walls. The bulb 153 for the cold control switch,'which is also the defroster, is located adjacent the outlet 152 of the upper evaporator, which extends downward at tube 154 and into the receiver 122 at 155.

A- suction tube 156 extends into the other end 123 of the receiver and is turned upwardly, having its opening 157 near the top of receiver 122.

The refrigeration system is shown in Fig. 6, and in additionto the two evaporators it includes the motor compressor unit having a motor housing 158, the lower portion 159 of which serves as an oil sump. The motor in the housing 158 is directly connected to the compressor 160,.which has its suctioninlet at 161 and-its pressure outletat162.

The compressor is adapted to receive lubricant from the sump 159 through a central bore or conduit 163; leading to compressor clearances and'compressor' inlet for pumping lubricant as well asrefrigerant-to lubricate the compressor and-motor. V I

An outlettube 164 extends from compressor outlet 162 through the wall of the sump 159,-and carries the compressed heated gaseous refrigerant directly to the precooler coils 165, which are diagrammatic and which extend to the precooler outlet 166, discharging into the top of the motor housing 158. In the precooler the gaseous, heated refrigerant and droplets of entrained oil are 'cooled and the refrigerant is partially condensed.

In the motor housing 158 the oil runs down over the motorv parts into the sump 159. The partially condensed refrigerant is revaporized, cooling the motor parts, and the gaseous refrigerant passes out a top outlet into' the tube 167 leading to the main condenser 168.

The main condenser 168 comprises a multiplicity of passes of tubing shown in detail in Fig. 7, and the main condenser results in the cooling and liquefaction of the refrigerant.

The outlet of the'main condenser is at 169 into a capillary tube 170, acting as a. restrictor for holding back the refrigerant. The capillary tube 170 is soldered to the suction tube 156 for heat exchange with this su'c tion tube, which is still cold and may be used to increase the efiiciency of the system by cooling the capillary tube 170'." The capillary 170 extends to the capillary inlet 136 of the lower evaporator 91,.completing the circuit.

The cold control, which also effects automatic defrosting-and is governed responsive to the bulb 153- by the cold control bellows switch 171, is so adjusted that it cycles between a temperature slightly above freezing, such as, for example, 34 degrees F. and a temperature below freezing, such as, for example, 20 degrees F.

The lower evaporator91' is coldest as it receives refrigerantfirst from the liquefying'unit, and it maintains the lower chamber25 at a temperature below zero'dc grees'F. Thisfreezing'chtrmbrds sealed against access of air by the rubber seal 77 about the lower door, and air circulation is substantially prevented by the insulating partition '26 so that there is little frosting insthe freezer chamber.

The upper chamber 24 for above-freezing food storage is maintained at suitable above-freezing temperatures which vary from the bottom of this chamber where meat is stored to a higher temperature at the. top of the chamber.

Although the chamber 24 is above freezing, the evaporator 98 goes below freezing to a temperature of, for example, 20 degrees F., and it, therefore, gathers frost from the moisture that enters the chamber 24 from the food stored therein and from the opening of the door. This frost is melted off by the warming of the upper evaporator 98 to a temperature above freezing, such as, for example, 34 degrees F. during each cycle; and at this temperature the defrosting control 171 also connects a defrosting electric heater 172 in circuit, heating the passes of refrigerant tubing on the upper evaporator and accelerating the defrosting by the action of the hot refrigerant.

Thus the upper evaporator is quickly defrosted once during each cycle of the motor compressor and the condensate is drained from the lower edge of upper evaporator 98 into the troughs 102, 103.

The condensate is delivered to the condensate pan 48, and this is slidably mounted on guides on the bottom panel 32, and the cool air passes in from the front, under the bottom panel 32, over the condensate pan 48 and upward about the motor compressor 44.

The precooler 165 and main condenser 168 are shown in greater detail in Fig. 7. The compressor and condenser are supported by a transverse channeled frame member 173, the ends of which have apertures 174 for receiving the screw bolts which secure it to the back panel 42.

This channeled member is bowed outwardly at its central portion 175 and supports the motor compressor at the bolts 176 which carry helical coil springs engaging brackets on the compressor housing.

The main condenser 168 comprises a multiplicity of horizontal passes of tubing 177, joined at their ends by U-shaped formations 178 and 179, and the outlet of the main condenser is indicated at 169 at the bottom. The inlet of the main condenser is at 167 at the top left.

The horizontal passes of tubing of the main condenser 168 are bent to a gradual curvature at 180, adjacent each end so that the U-shaped formations 178 and 179 are located adjacent the channeled member 173, and the lowermost pass 177 is supported by an outwardly bowed channeled member 181.

The curvature of the main condenser passes 177 forms a kind of vertical chimney 182, spaced from the rear panel 42 and providing space for upward circulation of air between the cabinet and the condenser. At its lower end the lowermost pass 177 is supported on the channel 181 by brackets 183, having rubber grommets about the tubing, and the cabinet also supports a pair of brackets 184 adjacent the top of the condenser and provided with rubber grommets surrounding the U-shaped bends.

The outlet 169 of the main condenser is connected to a drier 185, comprising a small metal shell containing silica gel confined therein by screens for absorbing any water in the refrigerant system.

All of the horizontal passes 177 of the main condenser are joined together and provided with additional heating radiating surface by a multiplicity of vertically extending wires 186', only a few of which are shown on the drawings, although the wires cover the condenser from side to side and are located on the inside and the outside in alignment with each other and welded to the tubing at each point where the wire crosses a tube. This greatly increases the heat radiation area of the main condenser 168.

The precooler zontal passes 187 165 comprises a multiplicity of horiof tubing which are shorter than those at twov points for supporting the precooler of the main condenser and which are joined together in one continuous length by U-bends 188. These horizontal passes 187 are arranged in two vertical banks 187 and 187a, and all the horizontal passes in each bank are welded to the vertically extending wires 189, located on both sides of the tubing and welded to the tubing at each point where the wire crosses a tube.

The precooler is supported inside the chimney space 190 and it is carried by a vertically extending frame member 191, having a rubber U-shaped grommet 192 extending about a horizontal pass 187 and having its ends confined in an aperture 193 in the vertical channel 191.

U-shaped rubber grommets 192 engage the channel191 165, and the channel 191 has its lower end secured to the motor compressor housing by screw bolt 194.

Thus the entire precooler and main condenser assem: bly is insulated by rubber from the cabinet.

The operation of the present refrigerator system is as follows:

The evaporators being in unrestricted communication with each other, the amount of refrigerant supplied to the system is sufiicient so that the upper evaporator receives only a limited amount of liquid refrigerant, and the above-freezing storage chamber is always maintained above 32 degrees F. Its temperature is controlled by a bulb 153, mounted on the upper evaporator, and the amount of tubing provided on the lower evaporator is such that the lower chamber is always maintained at a temperature around zero degrees F.

Each time the motor compressor operates responsive to the temperature of the upper evaporator the upper evaporator is cooled to about 20 degrees R, which is below freezing and, therefore, frost is accumulated.

Each time the upper evaporator warms to about 34 degrees F. the frost is melted ofi and the electric heater accelerates the heating of the upper evaporator and the refrigerant contained therein, causing the hot refrigerant to circulate and defrost the upper evaporator quickly.

The hot refrigerant never reaches the lower evaporator which is constantly maintained at zero degrees F.

Thus the evaporator in the above-freezing food storage compartment is automatically defrosted each cycle of the compressor, and condensate is carried to the condensate pan where it is evaporated.

While we have illustrated and described a preferred embodiment of our invention, many modifications may be made without departing from the spirit of the invention, and we do not wish to be limited to the precise details of construction set forth, but desire to avail ourselves of all changes within the scope of the appended claims.

Having thus described our new and desire to secure by States is:

1. A two door, two compartment household refrigerator comprising a single outer shell and a single inner liner spaced from each other by insulation, said liner being separated into a lower freezing compartment and an upper above-freezing compartment by an insulating partition, comprising a metal box containing insulation between its upper and lower walls, said upper wall forming a drain pan for gathering condensate and discharging it through a pipe, said partition being spaced from the liner side walls and rear wall, permitting condensate on the liner walls to run down to the bottom of the liner, which forms a drain pan with a central discharge opening, an insulated door for each compartment, each door having a rubber door seal surrounding the door, said shell having a face flange engaged by said door seals along three edges of each door, and the face flange surrounding the front opening in said shell, and the face flange being joined by a wide front partition breaker strip, engaged by the adjacent door seals at the edges of both doors at the partition, each door being formed of an outer shell invention, what we claim as Letters Patent of the United and an inner panel, having inwardly projecting ridges surrounding recesses, forming door shelves opposite the upper and the 'lowercompartments, 'an upper evaporator operating belowfreezingto cool the-upper compartment to above freezing temperature-andalso operating above freczing'to melt off 'frost during eachcycle, and located on the side walls and rear wall-of'the liner "at the upper end thereof, and comprising a metal sheet spaced from the liner by evaporator tubing, and draining from the lower edge of said sheet' to troughs on the liner wall which 'drain through hose to an evaporating'pan below the shell, also receiving condensate from the liner Walls and partition drain pan, and a below-freezing evaporator in the lower'compartment, having a horizontal ice tray he'lf'and a depending back wall, both receiving refrigerant-firstfrom'a' condensing unit.

2. A two door, two compartment'household refrigerator according to claim 1, in which the lower evaporator has cooling coils below its ice tray shelf and in front of its back wall, and a wire basket for frozen .food slidably mounted in said lower compartment and open at its 'front to permit the cooling of the contents of the frozen food shelves on the lower door.

References Cited in the file of this patent UNITED STATES PATENTS 2,167,442 Alsing July 25, 1939 2,672,030 Sc'hweller Mar. 16, 1954 2,687,625 Nadler Aug. 31, 1954 2,697,916 Alsing Dec. 28, 1954 2,745,259 Saunders May 15, 1956 2,773,362 Sc'heitlin Dec. 11, 19.56 2,797,553 Baillif .July 2, 1957 2,807,149 Williams Sept. 24, 1957 

